I think my iPhone has broken! HELP!

For the past couple of days, my iPhone 5s has been freezing, meaning that I have to force it to restart. I've had to restart it 4 times today because it had frozen. Then, I noticed that the names of some of the folders containing my apps no longer had a title, they had turned into what I can only describe as a box of pixels. I also have a lot of pictures and videos (some of which were very sentimental to me) on my phone which had all been deleted. This has happened to me twice before but they all usually restore within an hour or two. My mum suggested that I try to update my phone because I had an update that I hadn't done yet but as soon as I had accepted the T&Cs, it refused to install the update, despite the fact that I had managed to free up almost 3MB of space by deleting apps. I tried to do the same on my Mac but the same thing happened on that. My phone now won't switch on (it only displays the start up screen and then turns off) and won't charge at all despite having a perfectly good charger (it showed that my phone was on charge but the battery percentage was going down instead of up.) My Mac also won't allow me to back up my iPhone. Now, I'm really worried that my only option is to restore it to factory settings, but I'm scared that this may mean that I lose all of my pictures and videos for good. Is there anything I can do to at least get my iPhone to charge and turn on? Is there anyway that I can get my pictures and videos onto my computer if it won't turn on? Is there a possibility that my phone has been hacked or is my phone just bugging out? Thank you very much for any help that you provide! 🙂